The present invention relates to video measurement displays, and more particularly to a luminance qualified vector display for a video signal.
A vector display is a representation of the color components (i.e., R-Y, B-Y) of a video signal on a two-dimensional x-y plot. The vector display is typically used to setup cameras and other video sources using a standard color bar signal, for example. This is an incomplete representation of color space as there is no luminance (Y) information, so that both black and white map to the center of the display screen. Thus the color shows up the same on the vector display whether it is in shadow or bright light.
Other color space representations, such as the Tektronix “Lightning” and “Diamond” displays (U.S. Pat. Nos. 4,635,094 and 5,307,087), show both color and luminance, but are generally less accepted in the marketplace. Also many color correctors, such as those by DaVinci Systems, have track balls that move the colors in the same orientation as seen on the vector display.
What is desired is a modified vector display that takes into consideration luminance information to isolate black errors or to see an imbalance in whites.